• Title/Summary/Keyword: SINR

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User Association and Power Allocation Scheme Using Deep Learning Algorithmin Non-Orthogonal Multiple Access Based Heterogeneous Networks (비직교 다중 접속 기반 이종 네트워크에서 딥러닝 알고리즘을 이용한 사용자 및 전력 할당 기법)

  • Kim, Donghyeon;Lee, In-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.26 no.3
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    • pp.430-435
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    • 2022
  • In this paper, we consider the non-orthogonal multiple access (NOMA) technique in the heterogeneous network (HetNET) consisting of a single macro base station (BS) and multiple small BSs, where the perfect successive interference cancellation is assumed for the NOMA signals. In this paper, we propose a deep learning-based user association and power allocation scheme to maximize the data rate in the NOMA-based HetNET. In particular, the proposed scheme includes the deep neural network (DNN)-based user association process for load balancing and the DNN-based power allocation process for data-rate maximization. Through the simulation assuming path loss and Rayleigh fading channels between BSs and users, the performance of the proposed scheme is evaluated, and it is compared with the conventional maximum signal-to-interference-plus-noise ratio (Max-SINR) scheme. Through the performance comparison, we show that the proposed scheme provides better sum rate performance than the conventional Max-SINR scheme.

Performance Comparison of Exponential Effective SINR Mapping with Traditional Actual Value Interface for Different Transmission Schemes in OFDM Systems (OFDM 시스템에서 전송방법에 있어 Exponential Effective SINR Mapping 방법과 기존방법과의 성능비교)

  • Iqbal, Asif;Cho, Sung-Ho;Park, Jung-Min
    • Proceedings of the KIEE Conference
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    • 2008.04a
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    • pp.163-165
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    • 2008
  • In this paper we compare performance of exponential effective SINR mapping (EESM) with traditional actual value interface (AVI) approach for various modulation and coding schemes (MCS) in terms of coded bit error rate (BER) or block error rate (BLER) using different transmission schemes. This paper provides explanation and comparison of the two algorithms for single input single output (SISO), and single input multi-output (SIMO, 1X2) in OFDM systems. We calibrate the value of beta ($\beta$) in EESM using large number of channel realizations, here $\beta$ is a calibration constant. This paper also presents importance of beta value in EESM and how it improves the performance of OFDM wireless systems. We propose different modulation and coding schemes. Here we consider Standford university interim (SUI) channel models. Furthermore this paper also shows the detail observation of the two algorithms. Finally the conclusion review given for short summary.

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Greedy Heuristic Resource Allocation Algorithm for Device-to-Device Aided Cellular Systems with System Level Simulations

  • Wang, Xianxian;Lv, Shaobo;Wang, Xing;Zhang, Zhongshan
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.4
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    • pp.1415-1435
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    • 2018
  • Resource allocation in device-to-device (D2D) aided cellular systems, in which the proximity users are allowed to communicate directly with each other without relying on the intervention of base stations (BSs), is investigated in this paper. A new uplink resource allocation policy is proposed by exploiting the relationship between D2D-access probability and channel gain among variant devices, such as cellular user equipments (CUEs), D2D user equipments (DUEs) and BSs, etc., under the constraints of their minimum signal to interference-plus-noise ratio (SINR) requirements. Furthermore, the proposed resource-allocation problem can be formulated as the cost function of "maximizing the number of simultaneously activated D2D pairs subject to the SINR constraints at both CUEs and DUEs". Numerical results relying on system-level simulations show that the proposed scheme is capable of substantially improving both the D2D-access probability and the network throughput without sacrificing the performance of conventional CUEs.

Comparison Between Simulation and Test Result of Sigma-Delta STAP (Sigma-Delta STAP의 시뮬레이션과 시험 결과 비교)

  • Kwon, Bojun
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.29 no.6
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    • pp.457-463
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    • 2018
  • This paper compares the results of ${\Sigma}{\Delta}-STAP$ applied to actual radar test data and simulation data. The radar received a target signal from a virtual target generator and the clutter signal from a signal generator in an anechoic chamber. The simulation data were generated from ideal baseband radar signal modeling using the same parameter as that for the test radar. The ${\Sigma}{\Delta}-STAP$ results of the test and simulation data are similar in terms of the target signal shape and noise level. The SINR(Signal-to-Interfrence-plus-Noise Ratio) loss also had similar aspects, but the simulation result shows 1~2 dB higher SINR loss than the test result. This result verified that the simulation data can be a reasonable alternative test data when the ${\Sigma}{\Delta}-STAP$ is applied.

Performance of a Rectangular Smart Antenna in CDMA Basestation (CDMA 기지국에 설치된 평면 스마트 안테나의 성능 고찰)

  • Hong, Young-Jin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.3C
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    • pp.323-330
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    • 2007
  • Performance indicators such as output SNR, SIR, SINR for rectangular smart antennas in CDMA basestations have been derived. Simulations have been carried out to find the rectangular smart antenna performance while varying the input SNR, number of antenna elements, and the interferers' spatial distributions. Simplified Conjugate Gradient Method was chosen as the underlying beam forming algorithm. It has been shown that the performance of a rectangular smart antenna is similar to that of the linear one having the same number of elements when the interferers are randomly distributed over the whole azimuth angle range.

Performance Analysis of OFDMA Uplink Systems with Symbol Timing Misalignment (사용자간 상대적인 시간오차에 의한 OFDMA 역방향 시스템의 성능 분석)

  • Park Myonghee;Hong Daesik
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.42 no.2 s.332
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    • pp.17-22
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    • 2005
  • This paper presents our investigation for the effect of symbol timing errors in orthogonal frequency division multiple access (OFDMA) uplink systems. We express the symbol timing errors between users as the symbol timing misalignments with respect to the desired user. Then, we derive an explicit expression of the average effective signal-to-interference-plus-noise ratio. (SINR) as a function of the maximum value of the symbol timing misalignments. Based on the resulting SINR degradation, we evaluate the SINR gain with guard subcarriers in order to mitigate the effect of the symbol timing misalignments.

An Inter-Cell Interference Estimation Algorithm for Cellular OFDMA Systems (셀률러 OFDMA 시스템을 위한 셀간 간섭추정 알고리즘)

  • Rim, Min-Joong
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.43 no.10 s.352
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    • pp.55-59
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    • 2006
  • In cellular OFDMA(Orthogonal Frequency Division Multiple Access) systems, each subcarrier may suffer from different amount of interferences from neighbor cells. Suppose that it is possible to accurately estimate inter-cell interferences for each subcarrier, the performance can be considerably improved by applying SINR(Signal to Interference and Noise Ratio) weighting. This paper proposes an inter-cell interference estimation method for cellular OFDMA systems. The proposed method extracts amounts of noise and interferencesby eliminating the channel variation effects of pilot symbols caused by frequency offset, timing offset mobile velocity, and delay spread.

Analytical Evaluation of Almost Blank Subframes for Heterogeneous Networks (이종 네트워크를 위한 Almost Blank Subframes의 성능 분석)

  • Kim, Seung-Yeon;Lee, Hyong-Woo;Ryu, Seung-Wan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38B no.4
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    • pp.240-246
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    • 2013
  • In heterogeneous networks, the almost blank subframes (ABS) for inter-cell interference coordination (ICIC), which can be protected from the CCI due to unutilized subframes (i.e., ABS) is proposed. However, the analytical model for ABS-based systems has not been fully studied yet. In this paper, we derive a new analytical model to evaluate the performance of ABS-based systems. In an analytic model, we assume that each carrier in multicarrier systems, such as in OFDMA, is subject to large-scale fading, which is independent of other carriers. As a performance measure, we present the cumulative distribution function (CDF) for the effective SINR. We show the accuracy of the analytical model via simulation results.

Robust Cooperative Relay Beamforming Design for Security

  • Gong, Xiangwu;Dong, Feihong;Li, Hongjun;Shao, Wei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.11
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    • pp.4483-4501
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    • 2015
  • In this paper, we investigate a security transmission scheme at the physical layer for cooperative wireless relay networks in the presence of a passive eavesdropper. While the security scheme has been previously investigated with perfect channel state information(CSI) in the presence of a passive eavesdropper, this paper focuses on researching the robust cooperative relay beamforming mechanism for wireless relay networks which makes use of artificial noise (AN) to confuse the eavesdropper and increase its uncertainty about the source message. The transmit power used for AN is maximized to degrade the signal-to-interference-plus-noise-ratio (SINR) level at the eavesdropper, while satisfying the individual power constraint of each relay node and worst-case SINR constraint at the desired receiver under a bounded spherical region for the norm of the CSI error vector from the relays to the destination. Cooperative beamforming weight vector in the security scheme can be obtained by using S-Procedure and rank relaxation techniques. The benefit of the proposed scheme is showed in simulation results.

SINR based Maximum Link Scheduling with Uniform Power in Wireless Sensor Networks

  • Huang, Baogui;Yu, Jiguo;Yu, Dongxiao;Ma, Chunmei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.11
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    • pp.4050-4067
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    • 2014
  • In wireless sensor networks, link scheduling is a fundamental problem related to throughput capacity and delay. For a given set of communication requests $L=\{l_1,l_2,{\cdots},l_n\}$, the MLS (maximum link scheduling) problem aims to find the largest possible subset S of Lsuch that the links in S can be scheduled simultaneously. Most of the existing results did not consider bidirectional transmission setting, which is more realistic in wireless sensor networks. In this paper, under physical interference model SINR (signal-to-noise-plus-interference-ratio) and bidirectional transmission model, we propose a constant factor approximation algorithm MLSA (Maximum Link Scheduling Algorithm) for MLS. It is proved that in the same topology setting the capacity under unidirectional transmission model is lager than that under bidirectional transmission model. However, compared with some work under unidirectional transmission model, the capacity of MLSA is improved about 28% to 45%.